Question: $ { \left[\begin{array}{rr}{-2} & {-2} \\ {-1} & {0} \\ {1} & {0}\end{array}\right]+\left[\begin{array}{rr}{-2} & {2} \\ {4} & {4} \\ {0} & {3}\end{array}\right] = {?} } $
Solution: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{-2}+{-2} & {-2}+{2} \\ {-1}+{4} & {0}+{4} \\ {1}+{0} & {0}+{3}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{-4} & {0} \\ {3} & {4} \\ {1} & {3}\end{array}\right]}$